Tower By Numbers

Willis Tower is the premier corporate office building in Chicago, home to more than 100 companies including prominent law, insurance, transportation and financial services. The iconic building is the third tallest in the Western Hemisphere, encompassing more than 4.5 million square feet, including its Skydeck and 103rd floor glass viewing platform, The Ledge, which attract more than 1.7 million visitors every year, making it one of the top things for which Chicago is known.

Learn more about the tower:

Skydeck-39-1024x686 The Experience


The Ledge transforms how visitors experience Chicago. At 1,353 feet up, The Ledge’s glass boxes extend out 4.3 feet from the skyscraper’s Skydeck on the 103rd floor, providing never-before-seen views of the city. In fact, it’s safe to say that The Ledge offers Chicago’s best aerial view—and we know you’ll want to see it in person.

Willis Tower’s glass-floor observation box is just one of the attractions that draw people from all around the world to visit Skydeck. The tower itself is a world-renowned building, a Chicago icon, and a marvel of engineering. The eighth-tallest building in the world, it remains the third tallest building in the Western Hemisphere, standing 1,450 feet and 110 stories tall. Skydeck is also open for special events—and on the way up to the top, you can explore our completely unique, one-of-a-kind museum filled with interesting Chicago facts.


The Ledge brings an exhilarating new experience to Willis tower. Opened in 1974, the Skydeck attracts more than 1.7 million visitors annually who enjoy views of up to 50 miles and four states. Now, Skydeck dares visitors to attempt a new Chicago experience: stand on The Ledge and feel the city hum from 103 floors above Wacker Drive and the Chicago River.

The inspiration for Willis Tower’s glass-floor observation box came from the hundreds of forehead prints visitors left behind on Skydeck windows every week. Some come to replicate the memorable scene in Ferris Bueller’s Day Off, while curious children often go right up to the window. Whether you come as a family or come to get engaged, one thing is certain: you’ll definitely want to catch a glimpse below. Now they have a unique, unobstructed, and unforgettable aerial view of Chicago.

An unmatched view is not all the Skydeck offers. From the moment visitors arrive, they enjoy interactive and educational attractions that highlight the iconic building and celebrate Chicago’s sports, architecture, pop culture, history, food, music and people. Whether you come on vacation or visit during one of our special events, your time at Skydeck is guaranteed to leave a lasting impression.

Skydeck-58-300x270 The Experience

Skydeck Experience

Check out the Skydeck experience from the ground up after our recent renovation. Discover the best of Chicago as you make your way up to the 103rd floor.

The Tower

  • An all new, interactive 30-60 minute Chicago experience shares Chicago’s best and rich history prior to your 103rd floor Skydeck visit.
  • Challenge yourself with an interactive Chicago trivia game.
  • Marvel at the sheer scale of it all.


  • Breathtaking 1,353 foot simulated Ledge views from atop six of Chicago’s biggest attractions, like Wrigley Field.
  • Must-have, signature photo highlights of Chicago’s top locations.


  • Compare heights with the tallest structures in the world.
  • See just how many of you it would take to measure up to the height of Willis Tower.
  • Sneak a peek at the stunning views from The Ledge.


The original Sears Tower architecture firm, Skidmore, Owings and Merrill (SOM), designed The Ledge so that the fully enclosed glass boxes retract into the building, allowing easy access for cleaning and maintenance.

Experts in international structural glass design, Halcrow Yolles, fully designed and detailed all the glass and steel components. Beginning with the architect’s original concept, the engineers took the design one step further by eliminating all perimeter structural steel at the sides and along the floor of the glass enclosures, creating a near-invisible support system. 

MTH Industries is a 120-year-old Chicago-based glass and architectural metal contractor that installed the Cloud Gate in Millennium Park—and they also installed The Ledge’s 1,500 pound glass panels. Each box is composed of three layers of half-inch thick glass laminated into one seamless unit. The low-iron, clear glass is fully tempered for durability.

The Ledge, opened in July, 2009, was in engineering design for one year and then took six months of construction to complete.  Check out the attached video to learn more about the intricate design of Willis Tower’s glass-floor observation box.